'this'  operator is used to denote the current working 
object. 

 EX:
      Class student{
        public student(){
             this.addStudent();
        }
        public void addStudent(){
               //     to do code here
        }
        public static void main(String args[]){
           new student();
        }
      }
   
    'this' in the constructor is used to denote the current 
working object student...

The 'this' keyword in Java has the following uses:

1. To resolve ambiguity where a local variable hides a class
member. Example:

class MyClass {
    private int value;

    public MyClass( int value ) {
        // local variable 'value' hides class field 'value'
        this.value = value;
    }
}

2. To invoke one constructor overload from another. Example:

class MyClass {
    private int value;

    public MyClass( int value ) {
        this.value = value;
    }

    public MyClass() {
        // invoke MyClass( int value )
        this( 0 );
    }
}

3. To pass the current object instance as a parameter to a
method. Example:

class MyClass {
    private int value;

    public MyClass( int value ) {
        this.value = value;
        // pass current instance as a parameter to the method
        displayValue( this );
    }

    public static void displayValue( MyClass mc ) {
        System.out.println( "Value = " + mc.value );
    }
}

4. To invoke an outer class's non-static method from a
non-static inner class. Example:

class MyOuterClass {
    
    class MyInnerClass {
        public MyInnerClass() {
            // call the outer class's method
            MyOuterClass.this.displayText( "Inner instance
created" );
        }
    }

    public void displayText( String text ) {
        System.out.println( text );
    }
}

this is used to refer the current instance

this:
a. It call the overloaded(same class only)constructor
b.refer the current object.
c.U cant use 'this' in static method.